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``__builtin__`` --- Built-in objects
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This module provides direct access to all 'built-in' identifiers of
Python; for example, ``__builtin__.open`` is the full name for the
built-in function ``open()``. See chapter *Built-in Objects*.
This module is not normally accessed explicitly by most applications,
but can be useful in modules that provide objects with the same name
as a built-in value, but in which the built-in of that name is also
needed. For example, in a module that wants to implement an
``open()`` function that wraps the built-in ``open()``, this module
can be used directly:
import __builtin__
def open(path):
f = __builtin__.open(path, 'r')
return UpperCaser(f)
class UpperCaser:
'''Wrapper around a file that converts output to upper-case.'''
def __init__(self, f):
self._f = f
def read(self, count=-1):
return self._f.read(count).upper()
# ...
As an implementation detail, most modules have the name
``__builtins__`` (note the ``'s'``) made available as part of their
globals. The value of ``__builtins__`` is normally either this module
or the value of this modules's ``__dict__`` attribute. Since this is
an implementation detail, it may not be used by alternate
implementations of Python.